3&#39;-nitro-4&#39;, 6&#39;-dichloro-ortho-benzoyl-benzoic acid and process of making the same



Patented Apr. 30, 19 29.

UNITED STATES PATENT OFFICE.

IVAN GUBELMANN, HENRY J. WETLAND, AND OTTO STALLMANN, OF SOUTH MIL- WAUKEE, WISCONSIN, ASSIGNOBS TO THE NEWPORT COMPANY, A CORPORATION OF DELAWARE.

a-nrrnar, 6'-DICHLORU-ORTHO-BENZOYL-BENZOIC ACID AND rnocnss or MAKING mm sum No Drawing.

This invention relates to 3-nitro-4,6-dichloro-ortho-benzoyl-benzoic acid and to a process for making the same.

It is an object of our invention'to prepare 5 3-nitro-4,6-dichloro-ortho-benzoyl-benzoic acid in a simple and economical way, both because of the importance of the compound itself and more especially because of its value as a starting material for the synthesis of valuable dyest-ulf intermediates.

Other and further important objects of this invention will become apparent from the following description and the appended claims.

We have discovered that 2, l'-dichloro,-

ortho-benzoyl-benzoic acid can be nitrated with great ease by the use of a suitable nitrating agent, such as a mixture of sulphuric acid and nitric acid, or a nitrate, under certain conditions, to 3'-nitro-4,6-dicl1loro-ortho-benzoyl-benzoic acid.

The reaction is most probably best expressed by the following chemical equation 3-nitro-4,6'-dichloro-ortho-benzoyl benzoic acid is a white crystalline powder, slightly soluble in hot Water but practically insoluble in cold Water. It is easily soluble in glacial acetic acid and boiling alcohol, but quite insoluble in benzene and chloroform. It is 40 soluble in dilute caustic soda, sodium carbonate and ammonia solutions.

The sodium salt can be salted out from its solution by the addition'of an excess of caustic soda or by adding common salt. The free acid can be crystallized from alcohol and after repeated recrgstallization gives a melting point of 174 Application filed March 26, 1927. Serial No. 178,808.

Without limiting our invention to any partlcular procedure, the following example illustrates our preferred method of preparaion.

Ewampla-Into a flask equipped with an agitator are charged 500 parts of sulphuric monohydrate. While maintaining a temperature of 2025 0., there are then added'295 parts of 2,4-dichloro-ortho-benzoyl-benzoic acid and the mass stirred until all is in solution. The solution is then cooled to 10 C. and there are added 407 parts of nitrating acid, analyzing 17% HNO, and 87% H,SO,. After all the nitrating acid has been added the nitration mass is agitated for one hour longer. It is then poured into a mixture of 1000 parts of ice and 3000 parts of water and stirred until homogeneous. The product is then filtered off and washed with cold water until practically free of mineral acid. The yield is satisfactory. The melting point of the purified product is 174 C. We are aware that many changes may be made, and numerous details of the process may be varied through a wide range without departing from the principles of this invention, and we therefore do not purpose limiting the patent granted hereon, otherwise than necessitated by the prior art.

We claim as our invention: 1. As a new article of manufacture, 3'-nitrol,6-dichloro-ortho-benzoyl-benzoic acid,

having the following chemical constitution.

'2. A process of preparing 3'-nitro-4',6- dichloro-ortho-benzoyl-benzoic acid, which comprises treating 2,4-dichloro-ortho-benzoyl-benzoic acid dissolved in sulphuric acid monohydrate at a temperature of approximately 10 C. With a mixed nitrating acid, diluting with cold Water to precipitate the 3-nitro-4,6-dichloro-01'tho-benzoyl benzoic acid and isolating the same.

3. A process of preparing 3-nitro-4,6-

- dichloro-ortho-benzoyl-benzoic acid, which comprises treating 2' ,4-dich1oro-ortho-benzoyl-benzoic acid dissolved in sulphuric acid monohydrate at a temperature of approxi- '4,6'-dichloro-ortho-benzoyl-benzoic acid and isolating the same.

In testimony whereof, we have hereunto subscrlbed our names.

IVAN GUBELMANN. HENRY J. WEILAND. OTTO STALLMANN. 

